1 câu trả lời
Program GT;
Uses crt;
Var i,n: longint;
s: extended;
Function Gthua(a: longint):int64;
Var s,i: longint;
Begin
s:=1;
For i:=1 to a do s:=s*i;
Gthua:=s;
End;
Begin
Clrscr;
Write('Nhap n: '); Readln(n);
s:=0;
For i:=1 to n do
s:=s+(1/Gthua(i));
Write('Tong la: ',S:0:2);
Readln
End.
